Respuesta :

subtract 7x from both sides
3=9x-13-7x
simplify 9x-13-7x to 2x-13
3=2x-13
Add 13 to both sides
3+13=2x
simplify 3+13 to 16
16=2x
simplify both sides by 2
16/2=x
simplify16/2 to 8
x=8